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采用水热法合成法合成ZSM-11和ZSM-5分子筛,采用一步离子交换法制备了改性ZSM-11和ZSM-5系列催化剂。通过X射线衍射、电感耦合等离子体发射光谱和红外光谱对催化剂进行表征。结果表明:ZSM-5型催化剂负载的离子量高于ZSM-11型催化剂。催化剂中的共存离子Cu2+,Ce3+和Ni2+对两种类型分子筛振动所产生的影响不同,共存离子对ZSM-11的影响较大,表明2种类型分子筛骨架的结构存在差异。催化试验结果表明:Cu-ZSM-11催化剂催化稳定性高于Cu-ZSM-5催化剂。Ce3+和Ni2+改性的Cu-ZSM-11和Cu-ZSM-5催化剂的催化活性都有所提高,但Ce3+和Ni2+改性的Cu-ZSM-11催化剂的催化活性高于Cu-ZSM-11和对应的改性Cu-ZSM-5催化剂。随空速的增大,2种催化剂的催化活性先增大后减小,在空速约为0.6(g·s)/mL左右时达到最高活性。
ZSM-11 and ZSM-5 zeolites were synthesized by a hydrothermal synthesis method and the modified ZSM-11 and ZSM-5 catalysts were prepared by one-step ion exchange method. The catalysts were characterized by X-ray diffraction, inductively coupled plasma-atomic emission spectroscopy and infrared spectroscopy. The results show that the amount of ZSM-5 catalyst is higher than that of ZSM-11 catalyst. The effect of coexisting ions Cu2 +, Ce3 + and Ni2 + on the vibration of the two types of molecular sieves is different, and the influence of coexisting ions on ZSM-11 is larger, indicating that there are differences in the structures of the two types of molecular sieves. The catalytic test results show that the Cu-ZSM-11 catalyst has higher catalytic stability than the Cu-ZSM-5 catalyst. The catalytic activities of Cu-ZSM-11 and Cu-ZSM-5 catalysts modified by Ce3 + and Ni2 + all increased, but the catalytic activity of Cu-ZSM-11 catalysts modified by Ce3 + and Ni2 + was higher than that of Cu-ZSM- Corresponding modified Cu-ZSM-5 catalyst. With the increase of space velocity, the catalytic activity of the two catalysts first increased and then decreased, reaching the highest activity at a space velocity of about 0.6 (g · s) / mL.